Any reason why the Edelbrock guide plates won’t work on 690 heads. These heads have had the push rod holes drilled to .500 Thanks, Barry
Last edited:
Guide plates
- Thread starter Barry Taylor
- Start date
Dave, anyone other than showcars sell these.
I got mine from McQuillen.
Dave, James thank you very much!
Got some coming from Carl!
In my first post i said that that the guide plate holes were drilled to .500 what i ment to say was the pushrod holes had been drilled to .500 these heads had the Walden pedistal rocker seup install a long time ago. Put new valvesprings on and they wouldn’t clear the trunion of the rocker next to it by about 20 thousands. So going to conventional rockers. We could see on the older valvesprings where they were rubbing, hence possible reason for broken valve spring.
lennyjay
Well Known Member
Barry, if you are pulling the pressed in studs, check with Carl on how much the machinist will need to take off the stud bosses. My guy had to use a different ARP BB stud (flat, or flush bottom) to fit the plates. Also just because the ARP studs are new and considered the best do not over look them being bent. I found this out after installing my roller rockers (cranking motor by hand) and watching one roll totally to the side of the valve tip. I was measuring for pushrod length. I pulled the one stud and inserted in my drill press, low speed, sure enough it had a wobble, inserted a new one in the d. press and it ran straight. Put the new one back in the motor and the tip rolled down the center of the valve. Just a heads up.
Thanks for the heads up Lennyjay!
Yes they did. 
Not all rockers (or springs) are created equal. I had a nice set of Crowers that crashed a 1.550 spring, so I replaced them with some Scorpions that are a bit narrower and gave me some clearance. Scorpion was very helpful when I contacted them about dimensions.
lennyjay
Well Known Member
Tim, the poly lock treads were good all the way down. The stud that screwed into the head was ever so bent. I saw this because it pushed the pushrod hard against the slot in the guide. To go further I pulled the guide plate, put washers under the studs, and cranked the motor with the rockers back on. That was the only one that pushed the rocker off the valve tip. My machinist would not have seen it because he just did the heads.
Called Carl McQuillen wed. and ordered his pushrod guide plates. Got em by noon today and they were on in an hour. The quality, fit, finish of these are second to none. 
The ones I ordered were as well. 
No part# just order 690 guide plates. $80.00 A bargain!!! Better hurry before they go up.